This invention relates to the field of particulate blasting devices. More specifically, it relates to the field of devices for throwing abrasive particulate, such as, steel shot, grit, sand and the like, against a surface to be cleaned, abraded or otherwise treated. Typical of such devices are the centrifugal blasting wheels manufactured by Wheelabrator-Frye, Inc., Mishawaka, Indiana. These devices employ particulate to accomplish the treatment operations referred to and, in most cases, recirculate substantial portions of the particulate for further treatment whereby an efficient and low cost surface treatment is accomplished. Since the abrasive must be utilized for repeated cleaning operations it is necessary to know its useful life. As abrasive is used it begins to break down into small dust-like particles and loses its effectiveness. When this happens it is necessary to replace the particulate in order to maintain the efficiency of the treatment operation.
Accordingly, it is desirable to evaluate various kinds of particulate and even specific samples of a particular type to insure uniformity and that the particulate is up to specification. The present invention relates to a testing device capable of evaluating the useful life of a given sample of particulate. Shot testers, as they are often referred to, are known. However, the prior devices did not include structure for effecting substantially complete recirculation of the entire sample to insure reliability of the test results. Such prior devices are not necessarily closed systems nor is there any assurance that substantially all of the shot sample will pass through the throwing wheel during each test cycle. Other disadvantages of the prior devices include lack of portability and the complexity of the mechanism.
It is accordingly an object of the present invention to provide a shot testing device which employs a closed system for recirculating the shot sample under test.
Another object of the invention is to provide a shot tester wherein substantially all of the shot sample passes through the abrasive throwing wheel during each cycle of operation.
A further object of the invention is to provide a simple but effective means for returning the spent particulate back to the throwing wheel for further testing.
Another object of the invention is to provide a simple device for testing the useful life of blasting particulate.
Other objects and advantages of the invention will be apparent from the remaining portion of the specification.